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71.
聚酰胺—胺树枝状聚合物(PAMAM)作为一种新型超支化大分子聚合物,因其出色的化学和生物学特性,一直被众学者称之为“人工蛋白”。 PAMAM的特点是存在内部空腔,并含有大量的反应性末端基团,这些结构使得PAMAM可以被用作仿生大分子,模拟天然有机基质在牙体组织表面进行仿生矿化,即PAMAM作为有机模板调控矿物质成核以及晶体的生长,以此来建造比传统的异体材料更加理想的牙体修复材料。本文就 PAMAM 诱导牙体硬组织仿生矿化的研究进展作一综述。  相似文献   
72.
Background:Gastrointestinal complications and malnutrition are common problems that affect postoperative rehabilitation and survival of patients with esophageal cancer. Evidence has shown that probiotics have a positive effect on improving gastrointestinal complications and nutritional status of patients with esophageal cancer after surgery, but there is a lack of prospective studies on this topic. We designed this prospective randomized controlled trial to evaluate the effects of probiotics on gastrointestinal complications and nutritional status in patients with postoperative esophageal cancer.Methods:This is a prospective, randomized, double-blind, placebo-controlled trial. It was approved by the Clinical Research Ethics Committee of our hospital. 192 patients will be randomly divided into probiotics group and the placebo group in a 1:1 ratio. After operation, probiotics and placebo will be given orally for 8 weeks. The indexes of nutritional status and incidence of digestive tract complications will be recorded and the data will be analyzed by SPSS 18.0 software.Discussion:This study will evaluate the effect of probiotics on gastrointestinal complications and nutritional status of postoperative patients with esophageal cancer. The results of this study will provide clinical basis for the use of probiotics in postoperative treatment of esophageal cancer.Trial registration:OSF Registration number: D DOI 10.17605/OSF.IO/QHW86  相似文献   
73.
新型冠状病毒肺炎(COVID-19)具有强传染性、人群普遍易感性、高病死率等特点;而急性心肌梗死具有发病迅速、最佳救治窗口期短、病情危重等特点,其救治关键在于选择最佳策略以最大限度地提高再灌注效率。目前疫情防控形势严峻,对急性心肌梗死行急诊腔内介入治疗等临床工作也提出了新的要求。为规范救治流程,本研究对心血管医务人员的岗前培训,首诊COVID-19筛查,急性心肌梗死患者病情评估流程,以及急性心肌梗死行急诊介入手术的适应证、手术管理策略等进行了探讨。  相似文献   
74.
Introduction: Malnutrition increases the risk of cancer treatment-related complications. Nutritional intervention is beneficial for the outcomes of outpatients with cancer. This study investigated the impacts of nutrition consultation and care on energy intake and weight change in inpatients receiving cancer treatment.

Methods: We conducted a longitudinal study, enrolling 3221 inpatients with head and neck, lung, hepatobiliary, upper gastrointestinal, colorectal, breast, or gynecological cancer who received at least two nutrition consultations between April 2010 and July 2015. In every consultation, a dietitian calculated the total energy requirement and the actual energy intake was assessed using a 24-h dietary recall.

Results: Patients with head and neck cancer lost the most weight (1.16?kg/mo). For every consultation, a 0.03-kg weight gain per month was observed (P?=?0.001). The average energy consumption percentage (% estimated energy requirement) at the third consultation was 87.0%. After controlling for potential covariates, the energy consumption percentages at the third, fourth, fifth–seventh, eighth, and subsequent consultations were significantly higher than those at the first consultation (P?<?0.05).

Conclusion: For oncology inpatients, routine screening and at least three active nutrition consultations with dietitians effectively improved energy intake and preserved body weight.  相似文献   

75.
舌癌患者手术及放化疗后会出现构音障碍、吞咽困难、口腔黏膜炎、口干、营养不良等并发症,使患者生存质量下降,甚至导致肿瘤的复发转移,影响生存期,单一方法往往顾此失彼。依托于中国中医科学院西苑医院肿瘤康复基地,杨宇飞教授在国内外调研考察基础上,结合中国国情,构建了一种“门诊多学科肿瘤康复模式”,在舌癌康复方面,以患者为中心,以中医肿瘤内科为主导,多学科共同参与,结合康复科、口腔科、营养科、药剂科等各科优势,形成全程个体化规范序贯康复方案,对患者及早进行康复,在放疗前进行预防性干预尤其重要,使患者能够快速缓解手术和放疗的不良反应,患者获益明显。现取两个典型案例总结其舌癌多学科康复的经验,以期为舌癌的康复提供借鉴。  相似文献   
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78.
The analysis of quality of life (QoL) data can be challenging due to the skewness of responses and the presence of missing data. In this paper, we propose a new weighted quantile regression method for estimating the conditional quantiles of QoL data with responses missing at random. The proposed method makes use of the correlation information within the same subject from an auxiliary mean regression model to enhance the estimation efficiency and takes into account of missing data mechanism. The asymptotic properties of the proposed estimator have been studied and simulations are also conducted to evaluate the performance of the proposed estimator. The proposed method has also been applied to the analysis of the QoL data from a clinical trial on early breast cancer, which motivated this study.  相似文献   
79.
In low and middle-income countries mammographic breast cancer screening is prohibitively expensive and a cheaper alternative option is to use ultrasound as the primary screening test. In 2009, China launched a breast cancer screening programme for rural women aged 35–64 years with clinical breast examination coupled with ultrasound as the primary tool. Our study aimed to analyse the cost-effectiveness of breast screening compared to no screening among Chinese rural women. We developed a Markov model to estimate the lifetime costs and effects for rural women aged 35 years from a societal perspective. Asymptomatic women in the intervention arm were screened every 3 years before age 64 years. Breast cancer in the non-screening arm can only be diagnosed on presentation of symptoms. Parameter uncertainty was explored using one-way and probabilistic sensitivity analyses. Compared to no screening, breast cancer screening cost $186.7 more and led to a loss of 0.20 quality-adjusted life years (QALYs). Breast screening was more expensive and did harm to health among rural women with an incremental cost-effectiveness ratio (ICER) of $-916/QALY. The sensitivity analysis identified utility loss from false positives as the factor that most influenced the results, but this did not affect the conclusions. In a rural setting with such low breast cancer incidence, screening for asymptomatic disease is not cost-effective with current screening tools. Priority should be given to ensure that symptomatic women have proper access to diagnosis and treatment at an early stage as this will lead to mortality reductions without the usual screening harms.  相似文献   
80.
目的 通过阿霉素(Dox)复制大鼠慢性心力衰竭(CHF)模型,观察Liguzinediol对CHF大鼠心功能的影响。方法 通过血流动力学观察Liguzinediol对Dox(腹腔注射,2 mg/kg)诱导的CHF大鼠左心室内压最大上升/下降速率(±dp/dtmax)、左心室内压(LVSP)、动脉收缩压(ASP)、动脉舒张压(ADP)和心率(HR)的变化;观察Liguzinediol对血清一氧化氮(NO)、一氧化氮合成酶(NOS)、超氧化物歧化酶(SOD)、肿瘤坏死因子-α(TNF-α)和白细胞介素-6(IL-6)以及血浆中丙二醛(MDA)的影响。结果 Liguzinediol能增加LVSP、+dp/dtmax、ASP、ADP、AP、HR,降低-dp/dtmax(P<0.05~0.01);降低NO、iNOS以及MDA的浓度,同时增强了SOD的活性(P<0.05~0.01);抑制IL-6和TNF-α的生成(P<0.05~0.01)。结论 Liguzinediol可明显改善Dox诱导的CHF大鼠血流动力学指标,减少模型大鼠炎症因子的释放以及抑制氧自由基的生成。   相似文献   
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